Amazon, musicians friend, sweet water, etc. just look for speaker pads for reducing vibration. They were super cheep, like $20 and do a great job at isolating vibration and helping with speaker direction.
Many thanks for amazing video Plz help , I have this speakers ,my problem is after some time work , I found it very very very hot from back of speakers , what's can I do , it is normal or what , if l ignored this hot , it may be damage or what